/* 
 * Licensed to Aduna under one or more contributor license agreements.  
 * See the NOTICE.txt file distributed with this work for additional 
 * information regarding copyright ownership. 
 *
 * Aduna licenses this file to you under the terms of the Aduna BSD 
 * License (the "License"); you may not use this file except in compliance 
 * with the License. See the LICENSE.txt file distributed with this work 
 * for the full License.
 *
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 
 * implied. See the License for the specific language governing permissions
 * and limitations under the License.
 */
package org.openrdf.query.algebra.evaluation.iterator;

import info.aduna.iteration.CloseableIteration;
import info.aduna.iteration.LookAheadIteration;

import org.openrdf.query.BindingSet;
import org.openrdf.query.QueryEvaluationException;

/**
 * Wrap an inner iteration and suppress exceptions silently
 * 
 * @author Andreas Schwarte
 */
public class SilentIteration extends LookAheadIteration<BindingSet, QueryEvaluationException> {
	
	protected CloseableIteration<BindingSet, QueryEvaluationException> iter;
	
	public SilentIteration(CloseableIteration<BindingSet, QueryEvaluationException> iter) {
		super();
		this.iter = iter;
	}
	
	
	@Override
	protected BindingSet getNextElement() throws QueryEvaluationException {
		
		try {
			if (iter.hasNext())
				return iter.next();
		} catch (Exception e) {
			// suppress
		}
		
		return null;
	}

}
